Educational demonstration model

ABSTRACT

An educational demonstration model for demonstrating the principles of balance, and of the center of gravity, and the principles of the movement of the sun, the revolution of the earth around the sun, and the revolution of the moon around the earth. The device comprises a base with a substantially vertical member secured to and extending upwardly from the base, and with a spherical member balanced on the top of the vertical member and simulating the sun, and with members simulating the earth and the moon connected to the sun and mounted on rods so that they will revolve jointly around the sun and so that the moon will revolve around the earth. The large sphere is balanced on a point, and the smaller spheres representing the earth and the moon are connected to the sun by a rod so that they are offset from the center of the balance a distance so that the device may be balanced by means of a weight on the interconnecting rod and the center of gravity principle may be demonstrated. The smallest sphere representing the moon is mounted so that it may be made to revolve around the earth.

United States Patent 1 Nelson [4 1 Aug, 7, 1973 [541 EDUCATIONALDEMONSTRATION MODEL Primary Eraminer-lerorne Schnall [76] Inventor:Donald E. Nelson, 4105 Schirtzinger Cox Rd., Columbus, Ohio [22] Filed:Feb. 12, 1971 [57] ABSTRACT [21] Appl. No.: 114,949

[S2] U.S. Cl 35/45, 35/19, 46/131 [51] Int. Cl. (20% 27/02 [58] Field ofSearch 35/19, 43, 45, 46 R, 35/47; 46/131 [56] References Cited UNITEDSTATES PATENTS 1,355,799 10/1920 Bradish 46/131 X 1,996,600 4/1935 Vassv 46/131 2,551,668- 5/1951 Goosmann. 46/131 1,646,830 10/1927 Mueller46/131 743,483 11/1903 Gentry 35/45 858,977 7/1907 Hackeling 35/451,286,728 12/1918 O'Brien et al. 46/131 OTHER PUBLICATIONS StansiScientific Div., Catalog, Recd 2/20/1969, Q185F54 Gr. 336, Page 122.

An educational demonstration model for demonstrating the principles ofbalance, and of the center of gravity, and the principles of themovement of the sun, the revolution of the earth around the sun, and therevolution of the moon around the earth. The device comprises a basewith a substantially vertical member secured to and extending upwardlyfrom the base, and with a spherical member balanced on the top of thevertical member and simulating the sun, and with members simulating theearth and the moon connected to the sun and mounted on rods so that theywill revolve jointly around the sun and so that the moon will revolvearound the earth. The large sphere is balanced on a point, and thesmaller spheres representing the earth and the moon are connected to thesun by a rod so that they are offset from the center of the balance adistance so that the device may be balanced by means of a weight on theinterconnecting rod and the center of gravity principle may bedemonstrated. The smallest sphere representing the moon is mounted sothat it may be made to revolve around the earth.

1 Claim, 3 Drawing Figures PATENTEB 3, 750.308

sum 2 or 2 e/"ome E. Cox

EDUCATIONAL DEMONSTRA'ITON MOHEQEL BACKGROUND OF THE INVENTION Myinvention relates to an educational demonstration model for thedemonstration either of the principles of balance or the principle ofthe revolution of the earth around the sun, and the revolution of themoon around the earth, together with an indication of the movement ofthe sun in the universe.

Heretofore, educational devices have been provided for many purposesincluding devices for indicating the movement of the earth around thesun, and possibly the moon around the earth, but usually these have beencomplicated devices in which the earth is revolved around the sun bymeans of pulleys, belts, etc., and the movement of the earth controlsthe movement of the moon by gears, etc. Also, devices have beenheretofore devised in the nature of scales by which weights are balancedagainst each other to show the principle of balancing.

My device, however, is a very simple device by which the instructor caneasily demonstrate these principles without the requirement ofcomplicated gearing, belts, etc., and can by the one simple devicedemonstrate the several principles involved.

OBJECTS It is therefore an object of the invention to provide a device,simple in construction, inexpensive to manufacture, and yet effectiveand efficient in use, to serve as a demonstration model for thedemonstration (l) of the movement of the earth and the moon around thesun, and of the moon around the earth, together with the movement of thesun itself, and also (2) to demonstrate the principles of balance and ofcenter of gravity regardless of the weight of the objects and the lengthof the arms by which these objects are pivoted.

A further most important object of the invention is to provide a deviceof this character which is simple and easy to use.

Further objects and features of the invention will be apparent from areading of the following specification and claims when considered inconnection with the ac companying drawings illustrating preferredembodiments of my invention.

SUMMARY OF THE INVENTION I have found that the foregoing and otherobjects may be obtained by an apparatus wherein there is provided aneducational demonstration model comprising a base; an approximatelyvertical member secured to and extending upwardly from said base andhaving a flat surface at the upper end; a balancing device including arod having a pointed end which rests on said flat surface, and havingportions extending first outwardly, then downwardly, then inwardly, andthen upwardly; and a slidable weight positioned on a rod forming aportion of said balancing device. Preferably, the device is soconstructed that on one side of the pivot point there is a greaterweight than on the opposite side of the pivot point, but on the oppositeside there is a longer arm thus illustrating that a smaller weight mayby means of a longer arm balance a larger weight on the opposite sidehaving a shorter arm.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view in side elevation ofa device constructed according to my invention showing a base and a rodextending substantially vertically upwardly therefrom, having at itsupper end a flat surface on which there is balanced the pointed end of arod carrying a large sphere which is connected by rods to smallerspheres at the opposite side of the device;

FIG. 2 is a fragmentary showing of an alternative device in which aportion of the long connecting rod is curved so as to minimize contactthereof with the vertical supporting rod; and

FIG. 3 is a view in elevation of a balancing device in which there isprovided a curved rod extending substantially vertically upward from thebase and wherein there is balanced on the top of the curved rod anothercurved rod extending first outwardly, then downwardly, then inwardly,and then upwardly so that the device shows the principles of balance andcenter of gravity.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. ll of thedrawings, it may be seen that I have shown a base lll, having extendingsubstantially vertically upwardly therefrom a substantially straight rod112 having at its upper end a substantially flat surface l3. Balanced onthe surface 13 is a balancing device which consists of a large sphere 14simulating the sun, a smaller sphere R5 simulating the earth, and astill smaller sphere in simulating the moon, and interconnecting rods toallow the movement of the sphere M, the rotation of the sphere 15 aroundthe sphere M, and the rotation of the sphere 16 around the sphere 115.This linkage includes a pointed rod 17 which has its point contactingthe surface 13 and is thus balanced thereon. The rod 17 is connected atits opposite end to the sphere M. Also connected to the sphere M at apoint removed from the rod 17 is a bent rod 18. The rod w has adownwardly extending portion 21, a substantially horizontal portion 22and an upwardly extending portion 23. Surrounding the upwardly extendingportion 23 is a sleeve 24 into the upper end of which there is alsoinserted a bent rod 25. On the horizontally extending portion 22, thereis mounted a weight 26 for balancing purposes, and on the bent rod 25there is mounted a collar 27 to which there is secured a rod 2tsupporting the sphere 16. The upper end of the rod 25 supports thesphere 115. The upper ends of the rods 12 and ll2a may be provided witha disk of sandpaper such as the disk 13a shown in FIG. 2. Thecounterweight 311 tilts the structure so that normally the portion 22tends to move out of contact with the rod 12.

In FIG. 2, the horizontal portion 22a is provided with a semi-circularcurve 31a whereby it normally avoids contact with the upwardly extendingrod 12a.

Means are provided tending to keep the horizontal portion of thebalancing device separated from the vertically extending supporting rod.Thus in the embodiment shown in FIG. ll, the counterweight 31 tilts thebalancing device sufficiently that the portion 22 of rod 11% moves awayfrom the rod 12 (Le. away from the viewer). in the embodiment shown inFIG. 2, the curve 31a is sumcient to keep the parts 12a and 22aseparated.

Referring to FIG. 3, it may be seen that I have shown a base ill havinga substantially vertically upwardly extending support rod d2 (preferablycurved as shown but may be straight if desired) which has an uppersurface 43 on which there is balanced the pointed end 44 of a curved rod45. The rod 45 has an outwardly extending portion 46, a downwardlyextending portion 47, an inwardly extending portion 48 which extendspast the vertically upwardly extending rod 42 and merges into an upwardextending portion 49. Mounted on the curved rod 45 is a weight 51. Thedevice of FIG. 3 may be used to demonstrate the principles of balanceand of the center of gravity similarly to the device of FIG. 1 and thedevice of FIG. 2. The movement of the weight 51 will cause the rod 49 toassume various positions, in all of which positions the device willbalance at the point 44 on the surface 43.

The curved rod 45 is the balancing rod. The surface 43 is the flatsurface of the upright rod 42. The surface 43 is coated with a non-skidsurface or small piece of sandpaper or similar material. As thebalancing rod 45 moves up and down like an inverted teeter-totter, thenon-skid surface prevents the sharp point from walking off of thesurface 43. The curved rod 42 is fixed in the base 41 and curved in aplane perpendicular to the plane as shown by the rod 45. The deviceshown in FIGS. 1 and 2 is an alternative embodiment of the device shownin FIG. 3 inasmuch as it illustrates the same principles of balance andcenter of gravity, and also provides a model of the sun and moon bywhich the principles of the law of gravity and the attraction of theearth to the sun are illustrated. This is a demonstration of therelationship between the sun 14 and the earth 15 and the moon 16. Theconnecting rod 18 serves to illustrate the gravitational force of theearth to the sun. The earth can be rotated and can be tilted toillustrate the cause of the change of seasons. The device shown in FIG.3 demonstrates the principle of the center of gravity. The weight 51slides on the rod 45. The balancing rod balances in amazing positionsand imbeds this principle on a student's mind.

In using the apparatus to teach the movement of the moon around theearth, the bent rod 25 may be removed from the sleeve 24 and thesub-assembly consisting of rod 25 sphere l5, rod 28 and sphere 16 may beused to demonstrate the movement of the moon to around the earth 15.

The device shown in FIG. 3 may be used for several games. For example(1) rings may be hung on (or thrown onto) curved rod 45 without knockingit off balance; (2) baskets may be added to rod 45 and and balls such asping pong balls may be added (or thrown into) such baskets withoutknocking it off balance; (3) similarly targets may be added to rod 45and knocked down without disturbing the balance; and (4) trays may beadded on each side of rod 45 and tests may be made to find which of aplurality of balls weighs most with a minimum of weighing. Many othersimilar games may be devised.

It is to be understood that while the detailed drawings given describepreferred embodiments of my invention, they are for the purpose ofillustration only, and various changes may be made therein withoutdeparting from the spirit of the invention which is defined by thefollowing claims.

I claim:

1. An educational demonstration model for demonstrating both (1) theprinciples of balance and center of gravity; (2) the motion of the sunin the heavens, the revolution of the earth about the sun, and therevolution of the moon about the earth, comprising:

a base on which the whole apparatus rests;

an approximately vertical supporting rod secured to and extendingupwardly from said base and having a substantially flat surface at itsupper end;

a rod having a pointed end which rests on the flat surface and isrotatably balanced thereon;

a relatively large sphere representing the sun secured to the rod at theend thereof opposite to the pointed end;

a bent rod secured to said large sphere at a point removed from theconnection to the pointed rod, said bent rod consisting of asubstantially vertical portion extending downwardly from said sphere, asubstantially horizontal portion extending toward and beyond saidvertical supporting rod and an upwardly extending portion;

a sleeve into which said upwardly extending portion of the bent rod isinserted;

a third rod inserted in the end of said sleeve opposite to the upwardlyextending portion of the bent rod and extending upward from said sleeve;

a smaller sphere representing the earth secured to the upper end of saidthird supporting rod;

a collar mounted on said third supporting rod to rotate thereon;

a fourth rod secured to said collar to rotate about said third rod; and

a still smaller sphere representing the moon mounted on the end of thefourth rod opposite to the collar;

whereby the large sun sphere may move around said supporting rod, thesmaller earth sphere may move around said large sphere, and the smallestmoon sphere may move around said smaller earth sphere; and

a counter Weight comprising a slidable cylindrical member formed with alongitudinal axial bore, the horizontal portion of the bent rod passingthrough said bore, the weight being movably and slidably mounted on thehorizontal portion of the bent rod to maintain the apparatus in properrelationship.

1. An educational demonstration model for demonstrating both (1) theprinciples of balance and center of gravity; (2) the motion of the sunin the heavens, the revolution of the earth about the sun, and therevolution of the moon about the earth, comprising: a base on which thewhole apparatus rests; an approximately vertical supporting rod securedto and extending upwardly from said base and having a substantially flatsurface at its upper end; a rod having a pointed end which rests on theflat surface and is rotatably balanced theReon; a relatively largesphere representing the sun secured to the rod at the end thereofopposite to the pointed end; a bent rod secured to said large sphere ata point removed from the connection to the pointed rod, said bent rodconsisting of a substantially vertical portion extending downwardly fromsaid sphere, a substantially horizontal portion extending toward andbeyond said vertical supporting rod and an upwardly extending portion; asleeve into which said upwardly extending portion of the bent rod isinserted; a third rod inserted in the end of said sleeve opposite to theupwardly extending portion of the bent rod and extending upward fromsaid sleeve; a smaller sphere representing the earth secured to theupper end of said third supporting rod; a collar mounted on said thirdsupporting rod to rotate thereon; a fourth rod secured to said collar torotate about said third rod; and a still smaller sphere representing themoon mounted on the end of the fourth rod opposite to the collar;whereby the large sun sphere may move around said supporting rod, thesmaller earth sphere may move around said large sphere, and the smallestmoon sphere may move around said smaller earth sphere; and a counterweight comprising a slidable cylindrical member formed with alongitudinal axial bore, the horizontal portion of the bent rod passingthrough said bore, the weight being movably and slidably mounted on thehorizontal portion of the bent rod to maintain the apparatus in properrelationship.